Air-brake.



PATBN'TED MAY 28,

T. H. VAN DYKB.

AIR BRAKE.

APPLIOATION rum JULY 12. 1906.

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PATENTBD MAY 28 .1907.

T. H. VAN DYKE.

HAIR-BRAKE. APPLICATION FILED JULY 12. 1900.

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AIR BRAKE.

APPLIOATION FILED JULY 12. mop.

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' T. H.-VAN DYKE.

AIR BRAKE-Q APPLICATION rum) JULY 12. 1006. 6 flHBETS-SHEET Bl I20 I Ima -o Y v 6o lmnentur r J I r r": NORRIS PEYERS cc., wAsumamN, o. c.

UNITED STATES PATENT OFFICE.

THOMAS H.. VAN DYKE, OF KANSAS CITY, MISSOURI, ASSIGNOR OF ONE- THIRD TOJAMES DOARN AND ONE-THIRD TO LEE B. METTLER, OF

KANSAS CITY, MISSOURI.

AIR-BRAKE.

Specification of Letters Patent.

Patented May 28, 1907.

To all whom, it may concern:

Be it known that I, THOMAS H. VAN DYKE, a citizen of the United States,residing at Kansas City, in the county of Jackson and State of Missouri,have invented certain new and useful Improvements in Air-Brakes, ofwhich the following is a specification.

My invention relates to improvements in air brakes.

The objects of my invention are as follows To provide an apparatus bywhich substantially the same braking power may be applied to the pistonirrespective of the distance of piston travel; to provide means by whichthe slack is taken up with the same force regardless of the amount ofpower that is being applied to the brakes or as to Whether an emergencyor a service application is made; to provide a braking mechanism bywhich a plurality of consecutive braking applications may be madewithout having to recharge the auxiliary reservoir 'or braking cylinder,to provide an apparatus in which the amount of increase in train linepressure is not affected by the length of piston travel, whereby thebrakes on different cars maybe simultaneously released; to provide abrake mechanism by which brakes having a short piston travel are notapplied with a force above the normal; to provide a brake mechanism inwhich, when the brakes are applied and while the train is running withthe engineers brake valve on lap, the force of application of the brakeswill not be diminished by leakage; to provide means by which an excessof braking pressure is avoided; to provide a brake inwhich the amount ofair re quired to be used in making a braking application decreases withthe increase in distance of piston travel; to provide a mechanism which,when used for high speed braking an increased braking power may beobtained without increased train line pressure, said increase graduallyreducing as the train slows down; to provide a mechanism which may be soadjusted when used on loaded cars that an increase in braking power maybe obtained without increasing the train line pressure, said increase inbraking power not reducing as the train slows down.

Other novel features of my invention are hereinafter fully described andclaimed;

In the accompanying drawing illustrating the dotted line Yc-Z of Fig. 1.

my inventionFigure 1 is a vertical longitu-- 'Fig. 4 looking in thedirection denoted by arrow A. Fig. 6 is a side elevation view of thetriple valve and a portion of the braking cylinder, .the hand valve 100being removed. Fig. 7 is an elevation view looking at the inner side ofthe hand valve 100. Figs. 8 and 9 are elevation views of the valves 8and 9 respectively looking at the inner sides thereof. Fig. 10 is avertical sectional view taken on the dotted line mn of Fig. 1. Fig. 11is a vertical sectional View taken on Fig. 12 is a vertical sectionalview taken on the dotted line hc of Fi 4. Fig. 13 is a verticalsectional view ta en on the dotted line i 7' of Fig. 6. Figs. 14, 15, 16and 17 are vertical sections of the triple valve mechanism each taken onthe broken dotted line a, e, f and g in Fig. 4, looking in the directiondenoted by the arrow B. Fig. 14 shows the parts in the initial,charging, or release ositions. Fig. 15 shows the same parts in tliepositions occupied by them when slack is being taken up. Fig. 16represents the same parts in the posi tions occupied by them before thefull power has been applied to the brakes. Fig. 17 represents the sameparts in the lap position, in which position the brakes are set with theamount of power corresponding to the reduction of pressure in the trainline. Figs. 18, 19, 20 and 21 are views showing the relative positionsof the'rotary valves 8 and 9 and valve seat plate 7 when the parts arein the positions corresponding respectively to the positions representedby Figs. 14-, 15, 16 and 17.

In order to represent the ports which are circularly arranged in theseat plate 7 and rotary disk valves 8 and 9, in their proper relativepositions, the Figs. 18, 19, 20 and 21 represent the valves 8 and 9 andvalve seat plate 7 in section taken on the dotted circle q in Fig. 2,said circular section being then transversely divided on the dotted line1", s, in said figure and then laid out horizontally, as shown in Figs.18 to 21 inclusive.

Similar characters of reference denote similar parts.

1 denotes the braking cylinder having heads 2 and 3, the triple valvecasing 4 being attached to head 2. The casing 4 is provided with twochambers 5 and 6 separated from each other by a vertical partitionhaving a transverse hole in which is secured a plate 7 having oppositesides ground and providing seats respectively for two disk valves 8 and9 mounted oscillatively in chambers 5 and 6 on the horizontal bolt 10extending through the plate 7, the head of the bolt bearing against theouter side of the valve 8,

the threaded end of the bolt having mounted thereon nuts 11 against theinner one of which bears one end of a coil spring 12 the other end ofwhich bears against the valve 9, said spring serving to retain thevalves seated.

In the cylinder 1 is concentrically mounted a smaller cylinder 13 havingat its ends the'peripheral flanges 14 and 15 fitted in the cylinder 1,the flange 15 having holes 16 for the passage of air. Reciprocativelymounted in cylinder 1 is a piston having two heads 17 and 19reciprocatively mounted respectively in the two cylinders 1 and 13, apiston rod 18 connecting the heads 17 and 19, the

piston having further a portion projecting through the head 3 which isprovided with a central hole in which said projecting portion isreciprocatively mounted, said projecting portion having a diametersmaller than the piston head 19. The head 19 is adapted when in theposition shown in Fig. 1 to seat upon an annular resilient seat 20fitted to the inner rear periphery of the cylinder 13.

I will now describe how the projecting portion of the piston is securedto the piston rod 18. Reciprocatively mounted in the central hole in thehead 3 is a sleeve 22 having at its outer end a peripheral flange 23adapted to bear upon an annular seat 24 encircling said central hole. Onthe inner side of the head 3 encircling the sleeve 22 is a packing ring25 which bears upon said sleeve. The sleeve at its outer end is providedwith a transverse partition 26-having a central hole in which isslidably mounted the ordinary push rod 27 provided in the ordinarymanner at its outer end with means for being con nected with the brakelever, not shown. The inner end of the push rod 27 bears upon the solidinner end of the sleeve 22, said solid end being screw threaded andfitted to the outer screw threaded end of a cap 28, the inner end ofwhich is provided with a central hole in which is longitudinallyslidable the outer end of rod 18. In the cap 28 is a coil spring 29which encircles the rod 18 and. bears at its outer end upon a peripheralflange 31) at the outer end of the piston rod 18, and at its other endthe spring bears upon the inner end of the cap 28. The spring connectionso formed between the piston rod 11 and the projecting portion of thepiston, that is the sleeve 22, permits the flange 23 and piston head 19to seat simultaneously on the rings 25 and 20 respectively.

The piston head. 17 transversely divides the cylinder 1 into twochambers 31 and 32. Chamber 32 is connected by a passage 33 with chamber6. A passage 34 extending through casing 4, head and flange 14 connectschamber 31 with. a port 35 in seat plate 7. Chamber 21 is connected tothe ends ol' two passages 36 and 37, the opposite ends ol which areconnected with ports 33 and 39 in seat plate 7.

Oscillativcly mounted on the bolt 11) in chamber 5 is a bell crankgraduating valve 40, one arm of which. is mounted, between two shoulders42 on a horizontal slidable piston rod 43 one end of which extendsthrough a hole provided in the wall 44 inciosing one side of thechan'iber 5. This end oi the rod 43 outside said wall 44 is providedwith a piston 45 slidably fitted in a circular chamber 46 the upper sideof which adjacent the wall 44 is provided with a longitudinal groove 17through which the air admitted. to chamber 46 may pass the piston 45,when said piston is in the position shown in .lfiig. 1 1. in the wall 44are provided openings 48 through which air enters chamber 5 l'romchamber 46. 49 denotes a passage in casingl which at one endcommunicates with chamber '16 by an opening 50, the other end being theone to which is secured the train line pipe -19, which supplies thetriple valve with air from the engine. The opposite end ot the pistonrod 12-1 extends through. and is slidably mounted in an externallythreaded. cap 51 titted in the internally screw threaded inner end of ahorizontal tube 52 the inner end o1" which is titted in a threaded holein the wall 53 o1 chamber 5.

Encircling the rod 43 in the rap 51 is a coil spring 54 one end. ofwhich 1 ars against the cap and the other end bears against a washer 55mounted on the rod 43 and hearing at its outer side against an annularflange 56 on the inner periphery of the tube 52. )n the outer end of therod 43 is provided a 1 ad 57 which when an emergency appiiiaition ol'the brake is made bears against the washer 55 hard enough to move thewasher inward against the pressure oi the spring, an action which underordinary service can not talve place. At such emergency actions, the rod43 moving inwardly further, as hereinafter explained opens all the portsto a greater extent than ordinary, thus increasing the 1u iclr ness ofapplication o1 the ln'akes. The other arm of the bell crank valve 40 isadapted to enter an opening 58 in a housing 61 covering two ports 59 and60 in the disk valve 8. The ports 59 and 60 are adapted, When the valve8 is properly moved to register with the port 62 in plate 7 which portcommunicates with a passage in casing 4 leading to a chamber in saidcasing denoted by 63, which chamber is separated from chamber 6 by avertical wall 64.

Opposite the wall 64 is a wall 65. A horizontal piston rod 66 isslidably mounted in openings provided in walls 64 and 65. The piston rod66 at opposite sides of the wall 64 is provided with peripheral flanges67 which limit the movement in both directions of said rod. The Wall isprovided with openings- 68 connecting the chamber 6 with chamber 69. Inchamber 69 is a flexible diaphragm piston 70 the periphery of which issecured to the circular walls of chamber 69, said piston 70 beingcentrally secured to the piston rod 66. The chamber 69 is connected by apassage 71 with a port 72 in plate 7. Port 72, when the brakes are beingset is connected with. port 39 by recess 73 in valve 8, and said port72, is connected, during release or charging position with theatmosphere by means of recesses 73 and 76 in valve 8, ports 74 and 77 inplate 7, and passage 75 of easing 4, as shown in Figs. 8 and 12. Theport 77 also connects by passage 78 with chamber 63. Ports 77 and 62 areconnected with each other by a passage/7 9 in plate 7. In the left endof piston rod 66, as vie wed in Fig. 14, and at the right, as viewed inFig. 5, is provided a central longitudinal hole 80 in which is slid ablymounted a piston rod 81 to the outer, or right end as viewed in Fig. 5,are secured centrally two diaphragm flexible pistons 82 and 83, theperipheries of said. pistons being secured to the inner periphery of thewall of chamber 63. The said pistons are disposed between the wall 64and the passage 73, and the smaller of said pistons 82 is the same indiameter as piston 70. On the wall 64 is a projection 84 for limitingthe movement of the pistons 82 and 83. The rod 66 is pro vided with. twoshoulders 85 between which is disposed a pin 86 secured to the outerface of the disk valve 9. Longitudinal reciprocation of the rod 66oscillates said valve 9.

In the lower end of easing 4 is provided a cylindrical hole 87 in whichis mounted a piston 88 mounted on one end of a piston rod 89, the otherend of which rod is slidably mounted in a horizontal hole in aperipherally screw threaded disk 90 fitted in the threaded outer end ofthe hole 87, the extreme outer end of said hole being closed by a plug91. Encircling the rod 89 is a coil spring 92 one end of which bearsagainst the piston 88 and the other end bearing upon the disk 90. In thelower side of the cylindrical hole or chamber 87 is provided alongitudinal groove 93 which permits the air to pass the piston 88. Saidchamber 87 is connected by a passage 94 with-chamber 31 of the brakingcylinder. Said chamber 87 is connected upon the side of the pistonopposite to passage 94 to one end of a passage 95, the other end ofwhich is connected with a port 96, shown in Fig. 6. Adjacent the port 96is a port 97 communicating in the casing 4 with a passage 98 whichconnects with chamber 6.

Ports 96 and 97 may be connected with each other by a recess 99 providedon the inner side of a hand valve 100 oscillatively mounted on a stud101 secured to the outer side of the casing 4. Upon opposite sides ofthe stud 101 are two ports 102 and 103 which communicate with chamber 63at opposite sides of the large piston 83. Ports 102 and 103 may beconnected with each other by a recess upon the inner side of the handvalve 100. The recess 99 is large enough so that the hand valve may beturned to a position in which the ports 102 and 103 will be disconnectedwithout disconnecting the ports 96 and 97.

The valve 100 is held upon the stud 101 by means of a nut 105. Byoperating the hand lever 100 as hereinafter described the mechanism maybe adapted alternately for use on a loaded or empty car. Furthermore byproperly adjusting the said valve the apparatus may be used for highspeed service.

Referring to .Figs. 5, 8, 9, 12 and 14 ,061 denotes a port extendingthrough the valve 8 and which registers with port 107 in the plate 7,which in turn registers with the port 108 extending through the valve 9when the valves are in the release or charging positions shown in Figs.5 and 1.4. It will thus be seen that when the valves are as shown inFigs. 5 and 14 the air may pass from the train line into passage 49,thence through passage 50 into chamber 46, thence past piston 45 by wayof groove 47, thence into chamber 5 through the openings 48, thencethrough port 106, in valve 8, port 107 in plate 7, port 1.08 in valve 9into chamber 6 from which the air passes by way of port 41 in valve 9into port 35 in plate 7, thence by passage 34 into chamber 31, thuscharging at train pressure the chamber 31 lying to the left of pistonhead 17 as viewed in Fig. 1. Air from chamber 6 passes through passage33 into the forward end of cylinder to the right of piston head 17, asviewed in Fig. 1, which part of the cylinder is termed chamber 32. Itwill thus be seen that with air at train pressure in chambers 31 and 32,and chamber 21 being, as hereinafter described, connected with theatmosphere the larger area of piston head 19 over the area of crosssection of sleeve 22, will cause the piston head 17 together with pistonrod 18 and piston head 19 to move to the position shown in Fig. 1, whichis the release position, the piston head 19 being seated against ring 20and the flange 23 being seated against ring 24. Chamber 21 at this timeis connected with the atmosphere as follows :T he passage 36 connectingwith chamber 21 also connects with port 38 in plate 7, which port atthis position of the valves connects with recess 169, see Fig. 8, on theinner or ground side of valve 8, said recess 169 also registers at thistime with port 110 which extends through the seat plate 7 and registerswith recess 111, on the inner side of valve 9, see Fig. 9, which latterrecess also registers, when the valve 9 is in this position, with thearm 112 of a bifurcated port or passage 113 in the seat plate 7. Thepassage 113 connects with a passage 114 in casing 4 leading to theatmosphere.

During an emergency application, the train line discharges to theatmosphere as follows: The valves 8 and 9 having been forced to asuitable position as hereinafter related, the train line will dischargethrough passage 49 into passage 116 which connects with a port 117 inseat plate 7. This port 117 connects, when the valves 8 and 9 are in theemergency position. with a recess 118 on the inner side of valve 8.Recess 118 at this time registers with a port 119 extending clearthrough seat plate 7 and registering in the emergency position with therecess 120 in the inner side of valve 9, said recess 120 at the sametime registering with the other arm 115 of the bifurcated passage 113.The object of having the train line discharge, during an emergencyapplication through the passages 116 and 117 as described is to allow amore ready discharge of the air from the train line than could beaccomplished by having all the air in train line escape through theengineers valve, as is ordinarily done.

When it is desired to make a service application of the brakes, theengineer withdraws the desired amount of air from the train line, thusreducing the pressure in chamber 46 below what it is in chamber 5. Theexcess of pressure in chamber 5 acting on piston 45 will force thepiston rod 43 to the position shown in Fig. 15, in which position thepiston 45 will pass the end of groove 47 and prevent air passing fromchamber 5 to chamber 46. The rod 43 will move until the head 57 strikesthe washer when the spring 54 will hold the rod from further movement.The rod 43 in moving to the position shown in Fig. 15 swings thegraduating valve 40 against a pin 121 on the outer face of valve 8 androtates said valve to a position in which the port 106 will be cut oilfrom port 107 in plate 7, thus cutting chamber 5 off from chamber 6. Thevalve 8 being rotated to the position shown in Fig. 15 as justdescribed, will be in a position in which port 59 under housing 61 willregister, as shown in Fig. 19, with port 62 of plate 7. At the same timethat the valve 40 swings it will open passage 58 in the housing, asshown in Fig.

19, and the air will then pass trom chamber 5, through passage 58, intohousing 61, thence through port 59, when service application is made,otherwise during emergency application also through port 66, into port62, thence by passage 79 to port 77, thence by passage 78 into chamber63. ll the hand valve .100 is set for an empty car ports 162 and 163will be connected by .reeess 161-, and air in chamber 63 will accumulateat both ends of piston at a pressure substantially two and a half timesthe amount 01. pressure withdrawn from the train. line, the relativesizes of chambers 5 and 63 permitting this. Sutlicient air havingescaped from chamber 5 to chamber 68 so that air pressure in chamber 5is slightly less than in chamber 46 at right of piston 45, the pressurein chamber 46 will force the piston 45 to position shown in Fig. 16, inwhich position valve 46 will close opening 58 and shut otl chamber 63,but not re tracting valve 8. Valve 8 during its .lirst movement willhave shut oil chamber 21 from the atmosphere by disconnecting trom eachother ports 169 and 11.6, as shown. in Fig. 19. At the same time port 38will coin nect with port 35 by recess 169, thus permitting air fromchamber 31 to go by passages 34 and 36, see Figs. 1 and 12, into chamber21. At the same time ports 39 and 72 will be connected by recess 73 invalve 6 and air will pass from chamber 21 by passage 1'17. ports 39 and7;, and recess 73, into passage 71, and thence into chamber 69. Chambers21, 31 and 32 and also clnnnber 6, being thus connected, the pressure atboth sides 01' each piston head 1.7 and 19 will equalize, sleeve 32however, having an outward pressure upon it corresponding to thepressure in chamber 32 upon. the area, of the cross section. ol' saidsleeve. It will thus be seen that the outward pressure on sleeve 22 in.chamber 332 will force the piston heads 17 and 19 outward to av positionin which the slack willbe taken up and the shoes brought against thewheels. vl n the meantime chamber 69 will attain the same pressure as inchamber 6, that is the portion of chamber 69 on the side of piston nextthe passage 7.1. The pressure on that side of piston 76 will be greaterby the dill'erence in relative cross section between the large part ofthe piston rod 66 and piston 70, and the piston rod 66 will be forced tothe position shown in Fig. 16 at which. time the piston rod 66 willstrike the piston 82 and will be held from further movement until airhas been withdrawn from chamber 6. This is accomplished as lollows:*lhepiston rod 66 in moving rotates for the first time valve 9, by means ofshoulders 65 and pin 86 and positions valve 9 so that ports 41 and 35are disconnected, thus cutting oil chamber 31. from chamber 32, and atthe same time chamber 6 is connected with the atmosphere,

so that chamber 32 will discharge a part of 130 its air through passage33 into chamber 6.

. in Fig. 20. At this time port 123 in plate 7 is in register with arecess 124 on the inner side of valve 8 and recess 124 is at this timein register also with port 74, thus permitting the air to escape toatmosphere through passage 75, see Fig. 12; I

7 An amount of air will escape from chamber 6 that will exceed slightlythe amount of air that was let into chamber 63, for it is the air inthis chamber that held the piston rod 66 in the position shown in Fig.16. When the piston rod 66 is forced to continue its forward movement bythe greater pressure on the right, side of piston 70, as viewed in Fig.16, it will move to the poition shown in Fig. 17 in which position theflange 67 will seat against the wall 64. While the piston rod 66 ismoving this last described movement it will rotate the valve 9 stillfurther so as to cutoff port 122 from port 123, seeFig. 21.

When the air is withdrawnfrom chamber 32 by way of chamber 6 as justdescribed, the triple valve parts will be in the lap position, shown byFig. 17and Fig. 21. The piston heads 17 and 19 will now be forcedforward by whatever amount of pressure has been removed from chamber 32.It will be noted that with this brake only the air is lost that is takenafter the piston has moved to a position in which the slack is taken up,and that regardless of piston travel, substantially the same pressure isexerted upon the brake shoes. And as the brake is applied with theamount of air withdrawn from chamber 32 the nearer the outer end of thecylinder the piston moves in taking up the slack the less air isrequired to be taken from the chamber to set the brakes.

In the event that there is leakage of air past piston head 17 fromchamber 31 to chamber 32, the pressure in chamber 6 will cause thepiston rod 66 to be moved so as to again connect ports 122- and 123thereby letting air escape from chamber 6 corresponding to the amount ofleakage past piston head 17. There is therefore the same pressure uponthe piston to be used for applying the brakes as though no leakage tookplace.

To release the brakes after setting, the

train line pressure is increased, thus forcing the piston 45 to theposition shown in Fig. 14 thereby admitting air into chamber 5 and atthe same time turning valve 8 back to the position shown in Fig. 14,which action sets the ports so that port 109 again registers with port110, and port 110 being already in register'with a port 125 extendingthrough valve 9, the air passes from chamber 21 into chamber 6 and alsothrough passage 33 into chamber 32. The increase in pressure in chamber6 over that in chamber 69 causes the piston and piston rod 66 to returnto the position shown in Fig. 14, thus retracting the valve 9 anddisconnecting chamber 21 and chamber 6, but connecting chamber 21 withthe atmosphere as in the initial position first de* scribed, and at thesame time bringing ports 106, 107 and 108 into register so that the airwill pass therethrough and entering chambers 6 and 32, andsimultaneously with this chambers 31 and 32 are reconnected, the portsall having been reset to the positions shown in Fig. 18, which is therelease or charging position, corresponding to the positions shown inFig. 14. When the air has become equalized in chambers 5, 6, 31 and 32excess of pressure on the outer ends of piston heads 17 and 19 retractsthe piston to the positions shown in Fig. 1, in which position all theparts are ready for another braking application.

If for any reason it is desired to make a second application of thebrakes Without taking time for recharging, this may be done with mybrake for the reason that, after the first application, there is areserve amount of air in storage in chamber 31 and 32 sufficient to makea second application of the brakes. Illustrative of this it may bestated that if a full application of the brakes has been made at sayfifty pounds pressure on the brake piston, and the original charge inthe chambers 31 and 32 is approximately 70 pounds, the amount ofpressure required in my brake for an average piston travel would reducethe stored pressure to approximately fifty-nine pounds, thus giving areserve sufficient to make another full 50 pound braking pressure. Theabove has reference to the use of the brake with an empty car. If aloaded car is used, the pressure in chamber 32 should be reduced morethan in the case with an empty. To do this the hand valve 100 is turnedso that port 102 is cut off from recess 104, thus cutting out that partof chamber 63 to the right of piston 83, as viewed in Fig. 14. The

piston 83 being of greater diameter than piston 70, a greater amount ofair must be withdrawn from chamber 6 and therefore chamber 32 beforepiston 70 can force piston rod 66 from the position shown in Fig. 16 tothat shown in Fig. 17 where the chamber 6 is shut off from theatmosphere. When the hand valve is set so that the ports 102 and 103 areconnected, the ports 96 and 97 are connected by the recess 99 in valve100, thereby cutting in the reducing valve 88 in chamber 87 andpreventing the application at too great a pressure of the brakes ofanempty car. This is accomplished as follows:

When the hand valve 100 is positioned so that ports 9.6 and 97 areconnected, if the pressure in chamber 31 becomes too great the spring 92will yield and the valve or piston 88 ITO will move from its seat, thuspermitting air from chamber 31 to pass through passage 9 1 and passage93 into chamber 87 past the valve 88. The air will then pass by passage95, ports 96 and 97, recess 99 and passage 98 into chamber 6, and bypassage 33 to chamber 32. Spring 92 is adjusted so that valve 88 willwhen first opened by air pressure be disposed over the passage 93adjacent but not covering its reduced end, said passage graduallyincreasing in depth toward the seat of said valve. As the pressureweakens in chamber 31 the piston will move toward the seat and a largerspace will thus be provided in the passage 93 for the passage of airuntil finally the valve 88 will seat itself. Thus at the firstapplication of the brake, with the valve 100 set so as to cut in thereducing valve 88, a greater pressure will be applied to the brakes,which pressure will gradually reduce as the train slows down.

The disposition and size of the ports 102 and 103 and 96 and 97 andrecesses 99 and 104 are such that when used for an empty car the handvalve 100 is set so that ports 102 and 103, and ports 96 and 97 areconnected respectively. When used for high speed, valve 100 is shiftedto a position such that ports 102 and 103 will be cut offfrom'connection with each other, but ports 96 and 97 will be connectedwith each other so as to cut in the reducing valve 88. For use on aloaded car, the valve 100 is shifted so as to disconnect ports 102 and103 and also ports 96 and 97.

When an emergency application is made, the pressure in chamber 5 firstmoves the piston 45 and rod 13 to the position shown in Fig. 15, ashereinbefore described, but owing to the large amount of air being takenfrom the train line, in the emergency application, the excess pressurein chamber 5 will force piston 15 and rod 13 further to the right thanin a service application, and will therefore shift the valve 8 from theposition shown in Fig. 19 to one in which ports 117 and 119 will beconnected by recess 118, and, as already described, connecting the trainline by means of passages 49, 116 and 11 1 with the atmosphere, thusrelieving the train line of pressure at the triple valve. Ashereinbefore related, the service application will also move valve 8 sothat port will register with port 62 thus permitting more air to passinto chamber 63.

From the preceding description it will be noted that when the engineermakes a service application that train line pressure will be in the twochambers 31 and 32 of the braking cylinder 1 which is also the auxiliaryreservoir, and when the application is made by a reduction in pressurein the train line, valve 8 will be shifted so as to disconnect chambers5 and 6 with each other and at the same time disconnecting chamber 21from the atmosphere andv connecting it with. chambers 69 and 31. \Yhenchambers .11 and 21 shall equalize in pressure, which. will be after thepressure in 32, by acting on sleeve 22, has forced the piston heads 17and 19 together with sleeve 22 and push rod 27, to positions in whichthe slack will be taken up and the brakes applied to the wheels, thepressure in chamber 69 will force the piston and piston rod 66 to theposition shown in Fig. 16, thus shifting the valve 9 to a position inwhich cliai'nber 6 aml therefore chamber 32 by means of passage 33, willbe connected with the atmosphere and disconnected from chambers 31 and21. When an amount of air in pressure slightly below that that was firstadmitted into chamber 63 has escaped from chambers 6 and 32, thepressure in chamber 69 will force the piston rod 66, together with thealve 9 to the positions shown in Figs. 17 and 21, in which positions thevalves 8 and 9 will be in lap and the brakes will be held by the fullbraking pressure against the wheels. It now, the requisite pressure isapplied to the train line the valve 8 in the triple valve will beshifted again to the initial position shown in Fig. 11, thus connectingchambers 5 and 6 and chambers 21 and 32. The increase in pressure inchamber 6 will then shift valve 9, after piston heads 17 and 19 havebeen retracted to the position shown in Fig. 1 and again connectingchamber 21 with the atmosphere. The parts at this time will all be inthe position shown in Fig. 14 and another braking application may bemade when desircd.

Having thus described my invention, what I claim and desire to secure byLetters Patent, is:-

1. The combination with the braking cylinder, of the piston reci'irocatively mounted in the said cylinder, means connected with thepiston and. adapted to be connected wit it the brakeshoes for forcingthe brake shoes against the wheels'when the piston is moved to thebraking position, the train line. and means controlled by the reductionof pressure in the train line by which air stored in the brakingcylinder is applied to the piston during the piston travel at a uniformpressure irrespective of the amount of reduction in the train linepressure for moving thc piston from the release to the braking positionwithout the discharge of air from the cylinder to the atmosphere.

2. The combination with the braking cylinder, of the pistonreciprocactively mountcd in said cylinder, in ans connected with thepiston and adapted to be connected with the brake shoes for forcing thebrake shoes against the wheels when the piston is moved to the brakingposition, the train line, means controlled by the reduction of pressurein the train line by which air applied to the piston during pistontravel at a uniform pressure irrespective of the amount of reduction inthe cylinder, means by which air at train in the train line pressure formoving the piston from the release to the braking position, and means bywhich when the piston has reached the braking position in the cylindereffective braking pressure is applied to the piston proportionate to theamount of reduction of pressure in the train line and in a direction forforcing the brake shoes against the wheels.

3. The combination with the braking cylinder, of the pistonreciprocatively mounted in the cylinder, means by which air at trainline pressure may be introduced into the cylinder at both ends of thepiston, means by which a greater area at the forward end than at therear end of the piston may be subjected to the air pressure, therebyforcing the piston to the rear or release position, and means by whichthe air pressure may be applied to a greater area at the rear than atthe forward end of the piston, whereby the piston will be forced fromthe release to the braking position.

4-. The combination with the braking cylinder, of the pistonreciprocatively mounted in the cylinder, means by which air at trainline pressure may be introduced into the cylinder at both. ends of thepiston, means by which a greater area at the forward end of the pistonthan at the rear end thereof may be subjected to the air pressure,thereby forcing the piston to the rear or release position, means bywhichthe air pressure may be applied to a greater area at the rear endof than at the forward end of the piston, whereby the piston will beforced forward from the release to the braking position, and means bywhich when the piston has reached the braking position air will bedischarged to the atmosphere from the cylinder forward of the forwardend of the piston.

5. The combination with the braking cylinder, of the pistonr'eciprocatively mounted in the cylinder, means by which air at trainline pressure may be introduced into the cylinder at both ends of thepiston, means by which a greater area at the forward than at the rearend of the piston may be subjected to the air pressure, whereby thepiston is forced from the forward or braking to the release position,means actuated by reduction in the train line pressure by which agreater area at the rear than at the forward end of the piston may besubjected to the air pressure, whereby the piston may be forced from therelease to the braking position, and means by which when the piston hasreached the braking position air proportionate to the amount ofreduction in the train line pressure will be discharged to theatmosphere from the cylinder forward of the forward end of the piston.

6. The combination with the braking cyl inder, of the pistonreciprocatively mounted line pressure may be introduced into the cylinder at both ends of the piston, means by which a greater area at theforward than at the rear end of the piston may be subjected to the saidair pressure, whereby the piston will be forced from the brakingposition to the rear or release position, means actuated by reduction inthe train line pressure by which a greater area at the rear than at theforward end of the piston may be subjected to said air pressure, wherebythe piston will be forced forward to the braking position from therelease position, means by which when the'piston has reached the brakingposition air will be discharged to the atmosphere from the cylinderforward of the piston and proportionate to the reduction in train linepressure, and regulatable means for controlling the proportion of theair so discharged relative to the train line reduction.

7. The combination with the braking piston, of the train line, means forapplying air at the same degree of pressure from the train line toopposite ends of the piston and alternately over different areas at saidends, the pressure in the train line controlling at which end thegreater area is subjected to the said air pressure.

8. The combination with the braking piston, of the train line, means forapplying air at the same degree of pressure from the train line at theforward and rear ends of the piston and alternately over different areasat the ends, whereby the piston is moved toand from the brakingposition, the pressure in the train line determining at which endthegreater area is subjected to the air pressure, said means providingwhen the piston has reached the braking position a reduction in pressureat the forward end of the piston proportionate to the reduction made. inpressure in the train line.

9. The combination with the braking piston, of the train line, means forapplying air from train line at same degree of pressure at the forwardand rear ends of piston and alternately over different areas at theends, thereby the piston is moved to and from the braking position, thepressure in the train line determining at which end the greater area issubjected to the air pressure, said means providing, when the piston hasreached the braking position, a reduction in pressure proportionate tothe reduction in pressure in the train line, and adjustable means forvarying the proportion of reduction in pressure at the forward end ofthe piston relative to the reduction. in pressure in the train line.

10. The combination with the braking piston, of the train line, meansfor applying air at the same degree of pressure at the forward and rearends of the piston from the-train line and alternately over differentareas at the ends, whereby the piston is moved to and from the brakingposition, the pressure in the train line determining at which end thegreater area is subjected to the air pressure, said means providing whenthe piston has reached the braking position a reduction in pressure willbe made at the forward end of the piston proportionate to the reductionof pressure made in the train line, and means by which the excess ofpressure at the rear end over that at the forward end of the piston maybe automatically limited to a predetermined amount.

1 1. The combination with the braking piston, of the train line, meansfor applying air from the train line at the same degree of pressure atthe forward and rear ends of the piston and alternately over differentareas at the ends, whereby the piston is moved to and from the brakingposition, the pressure in the train line determining at which end thegreater area is subjected. to the air pressure, said means providing,when the piston. has reached the braking position, a reduction inpressure at the forward end of the piston proportion to the reduction ofpressure in the train line, and adjustable means by which the eXcess ofpressure at the rear end over that at the forward end of the piston maybe automatically limited.

12. The combination with the braking piston, of the train line, meansfor applying air from the train line at the same degree of pressure atthe forward and rear ends of the piston and alternately over differentareas at the ends, whereby the piston is moved to and from the brakingposition, the pressure in the train line determining at which end thegreater area is subjected to pressure, said means providing that whenthe piston has reached the braking position a reduction in pressure willbe made at the forward end of the piston proportionate with thereduction of pressure in the train line, adjustable means for varyingthe proportion of reduction in pressure at the forward end of the pistonrelative to the reduction in pressure in the train line, and automaticmeans for limiting the excess of pressure at the rear over that at theforward end of the piston.

13. The combination with the braking piston, of the train line, andmechanism intermediate the train line and piston by which air at thesame degree of pressure may be applied from the train line at theforward-and rear end of the piston and alternately over different areasat said ends, said mechanism having means by which when a sufficientpressure is made in the train line the greater area under pressure willbe at the forward end of the piston and when a reduction of pressure ismade in the train line air will be transferred from the forward end ofthe piston to a greater area at the rear end of the piston, thus movingthe piston to the braking position, said mechanism providing that whenthe piston has reached the braking position, air at the forward end ofthe. piston will be released to the atmosphere reducing the pressure atthe forward end of the piston proportionate to the reduction of pressurein the train line.

I l. The combination. with the braking piston, of the train. line, andmechanism by which when sufficient pressure made in. the train line airtherefrom will be applied at both ends of the piston the greater area ofpressure being at the forward end of the piston, said mechanismproviding that when a reduction of pressure is made :in the train lineair will be transferred. from the forward to the rear end of the piston.and against a greater area at the rear than at the forward end, thusmoving the piston to the braking position, said mechanism providing alsothat when the piston has reached the braking position air proportionatein pressure to the reduction of pressure in. the train line will bedischarged from the forward end of the piston to the atmosphere, meansalso being provided by said mechanism by which whenv sufficient pressurehas again been placed in the train line air from the train line will beapplied at both. ends of the piston but over a greater area at the'fOIWtlltl end thereof, thus moving the piston from the braking to therelease position.

15. The combination with the braking pis ton, of the train line, andmeans by which air is applied. at the forward and rear ends of thepiston, said means providing that when a reduction of pressure is madein the train line air at a substantially uniform pressure will beapplied over a greater area at the rear than at the forward end of thepiston during the piston. travel to the braking position.

16. The combination with the braking piston, of the train line, andmeans by which air is applied at the forward and rear ends of thepiston, said means providing that when a reduction of pressure is madein the train line, air at a sul st' antially uniform pressure will beapplied over a greater area at the rear than at the forward end of the.piston during the piston travel to the braking position, said meansproviding that when the piston has reached the braking position pressureof air proportimrate to the reduction in pressure in the train. linewill be removed from the forward end of the piston.

17. The combination. with the braking piston, of the train line, andmeans by whieh. air is applied at the forward and rear ends of thepiston, said means providing that when a reduction of pressure is madein the train line, air at a substantially uniform pressure will beapplied to the rear end of the piston and ever a greater area. than atthe forward end and during the whole of the piston travel, said meansproviding that vIOO when the piston has reached the braking poandoutside of the smaller cylinder, the larger 6 5 sition air proportionateto the reduction in pressure in the train line will be removed from theforward end of the piston, said means providing also that when pressurehas been sufficiently increased in the train line a greater area at-theforward than at the rear end of the piston will be subjected to the airpressure, thusretracting the piston from the raking position. 7

18. In air brakes, the combination with two cylinders of difierentdiameters, the smaller cylinder communicating at its forward end withthe larger cylinder, both ends of the larger cylinder and the rear endof the smaller cylinder being closed, the larger cylinder having airpassages communicating respectively with its forward and'rear ends, andthe smaller cylinder having means for conveying air to and from its rearend, of the braking piston having two heads reciprocatively mounted inthe larger and smaller cylinders respectively, the larger head beingintermediate the air passages of the larger cylinder and the. smallerhead being forward of the air conveying means of the smaller cylinder,the piston having a portion forward of the larger head projectingthrough the forward end of the larger piston, said projecting portionhaving a diameter smaller than the diameter of the smaller head, meansconnecting with said projecting portion of the piston for applying thebrakes, valve mechanism connecting with said air passages and with theair conveying means leading to the smaller cylinder, and meanscontrolled by and adapted to be connected with the train pipe by whichsaid valve mechanism is actuated to control the passage of air throughsaid passages and air conveying means.

19. In air brakes, the combination with the piston having two heads ofdifferent diameters, of two cylinders in which said heads arereciprocatively fitted, the smaller cylinder communicating with thelarger cylinder at the forward end of the smaller cylinder, the largercylinder being closed at both ends and the smaller cylinder closed atits rear end, the piston at the end forward of the larger head having aportion of smaller diameter than the smaller head and projecting throughthe forward end of the larger cylinder, the larger cylinder having airpassages leading to it forward and rearward of the larger head of thepiston, the smaller cylinder having air passages leading to itat therear of the smaller piston head.

20. In air brakes, the combination with two cylinders, one locatedwithin the other, the smaller cylinder at its forward end communicatingwith the larger one, and the larger cylinder being closed at both ends,the rear end of the larger cylinder having air passages extendingtherethrough at the inside cylinder having an air passage communicatingwith it adjacent its forward end, of apiston having two headsreciprocatively mounted in said two cylinders, the piston forward of thelarger head havin a portion smaller in diameter than the smal er headand projecting through the forward end of the larger cylinder. I

' 21. In air brakes, the combination with two cylinders of differentdiameters the smaller communicating with the larger at the forward endof the smaller cylinder, the

larger cylinder being closed at both ends and the smaller cylinderclosed at its rear end, the smaller cylinder having an annularperipheral seat at its rear end, and the larger cylinder at its closedend having a central hole and on its outer side encircling said hole anannular seat, of the piston having two heads fitted reci ro'cativelyrespectively in said cylinders, t e piston forward of the larger headhaving a projecting portion extending through said hole and having anan: nular flange adapted to rest against the seat encircling said holewhen the piston is retracted, the smaller head of the piston beingadapted to bear upon the annular seat in the smaller cylinder when thepiston is retracted, the larger cylinder having air passagescommunicating with it forward and rearward of the larger piston head,the smaller cylinder having air passages communicating withit to therear of the smaller istpnhead and within the annular seat in t e smallercylinder.

22. In air brakes, the combination with the braking piston, of means bywhich the piston is moved to and from the braking position by airpressure derived from the train pipe and appl ed at opposite ends of thepiston, and. automatic means for limiting the preponderance of pressureat' one end over the pressure at the other end of the piston.

In air brakes, the combination with the braking piston, of means bywhich air derived from the train pipe may be applied at opposite ends ofthe piston simultaneously, means controlled by train pipe pressure bywhich alternately a greater area at one end of the piston may besubjected to the air pressure than is applied at the opposite end,thereby forcing the piston to and from the braking position, andautomatic means for limiting the preponderance of pressure at one endover the pressure at the other end.

24. In air brakes, the combination with the braking piston, of means bywhich air derived from the train pipe may simultaneously be applied toopposite ends of the piston,

means controlled by pressure in the train pipe by which alternately oneend of the piston may be subjected to greater pressure than the otherend, and automatic means by LOO IIO

.be applied to opposite ends of the piston,

means controlled by pressure in the train pipe by which opposite endsare alternately subjected to a preponderance of pressure one end overthe other, and regulatable means by 1 which is automatically limited thepreponderance of pressure at one end ol" the piston over that at theother end.

26. In air brakes, the combination with thebraking piston, of means bywhich air derived from the train pipe may simultaneously be applied toopposite ends of the piston, means controlled by pressure in the trainpipe by which opposite, ends of the piston may each alternately besubjected to pressure over a greater area than the area of the oppositeend subjected to pressure, and regulatable automatic means for limitingthe preponderance of pressure at one end over that at the other end.

27. In air brakes, the combination with the braking piston, of meansbywhich air derived from the train pipe may be simultaneously applied toopposite ends of the piston, means by which when the train pipe pressureis reduced a greater pressure will be applied at one end than at theother end 01' the piston, thereby forcing the piston to the brakingposition, means by which when the piston ias reached the brakingposition air will be discharged from said other end of the piston andautomatic means by which the diflerence in pressure at opposite ends maybe limited.

28. In air brakes, the combination with the braking piston, of meansbywhich air derived from the train pipe may be simultaneously applied toopposite ends of the piston, means by whichwhen the train pipe pressureis reduced air pressure will be transferred from one end of the pistonto the other end thereof, thereby forcing the piston to the brakingposition, and means by which, when the piston has reached the brakingposition, air pressure proportionate to the reduction of pressure in thetrain pipe may be reduced at the end of the piston from which the airpressure was transferred.

29. In' air brakes, the combination with the braking piston, of means bywhich air derived from the train p pe may be simultaneously applied toopposite ends of the piston, means controlled by train pipe pressure bywhich oppositeends of the piston are subjected alternately to apreponderance of pressure at one end over that at the other end wherebythe pistonmay be moved to and from the braking position, and means bywhich, when the piston has reached the braking position, air pressureproportionate to the reduction ol pressure in the train pipe will bewithdrawn 'lrom the end ol' the piston having at the time the leastpressure against it.

30. In air bra-lies, the combination with the braking piston, oli meansby which air derived from the train pipe may be simultaneously appliedto opposite ends ol the piston, means controlled by trainpipe pressureby which opposite ends ol" the piston may each alternately be subjectedto air pressure over an area greater than that subjected to pressure atthe opposite end, whereby the piston is moved to and from the brakingposition, and means by which, when the piston has reached the brakingposit ion, air pressure proportionate to the reduction ot pressure inthe train pipe will be withdrawn from the end ol the piston which. atthe time has the smallest area subjected to pressure.

31. In air brake the cmnbination with the braking piston, ol m ans bywhich air derived from the train pipe may be applied to opposite endsol" the piston, means con trolled by pressure in the train pipe by whichopposite ends ol the piston may be subjected each alteri'iately to airprcssu re over a greater area than the area (it the opposite end.subjected to the air pressure, whereby the piston is moved to and fromthe braking position, means by which when the piston has reached thebraking position air pressure proportionate to the reduction ol pressurein the train pipe will be withdrawn from the end of the piston which. atthe time has the smallest area exposed to the air pressure, andregulatable means tor varying the proportion. withdrawn relative to thereduction in the train pipe.

32. In air brakes, a triple valve compris ing a casing having twochambers one provided with means tor being connected with the train pipeand the other provided with means for being connected with the brakingcylinder, a passage connecting the chambers with each. other, meanscontrolled by the train pipe pressure controlling the admission of airto the chamber having the means for connecting it with the train pipe, avalve actuated by said controlling n'ieans and controlling the passageconnecting the two chambers, a second valve controlling the passage olair between the braking cylinder and the chamber connected with. thebraking cylin der, and means actuated by the lirst named valve forcontrolling the action ol" the second named valve.

In air brakes, a triple valve comprising a casing having two chambersand passages leading from one chamber to the at mosphere and to thebraking cylinder, :1. passage leading trom the other chamber to thetrain pipe, means controlled by the. train pipe pressure controlling theadmission ol air from the train pipe to the chamber connected with it, apassage connecting the two chambers, a valve controlling said passageand actuated by the means controlling the admission of air from thetrain pipe with the chamber connected with it, a second valvecontrolling the passages leading from the chamber connected with thebraking cylinder, and means actuated by air pressure and controlled bythe first named valve for actuating the second named valve.

34. In air brakes, the triple valve comprising a casing having chambers5 and 6, means for connecting said chambers respectively with the trainpipe and with. the braking cylinder, a passage connecting the twochambers, a valve controlling said passage, means controlled by trainpipe pressure for actuating said valve, a second valve controlling themeans connecting the braking cylinder with the chamber 6, chambers 63and 69, pistons 82 and 83 mounted in chamber 63, piston 70 mounted inchamber 69, passages connecting chamber 69 with chambers 5 and 6 respecTHOMAS H. VAN DYKE.

Witnesses:

R. E. HAMILTON, E. B. HoUsE.

